Case Environmental
Case Environmental

Chlorination Certificates & Disinfection

As we are key workers we are continuing to work during the third lockdown.  We will follow appropriate precautions and expect our clients to do the same.


Disinfection/chlorination of premises following Covid Lockdowns

UK Government guidance is to treat plumbing systems that have been out of regular use (and not flushed weekly or where the control regime has not been effective) as a new system and chlorinate prior to using.  The requirement for chlorination can be as little as two weeks out-of-use and as such many business and educational premises may require this service following lockdown when reopening.  It is recommended that this is carried out a week before the buildings are in use again.  Please contact us if this is a service you may require.


Why Case Environmental?  We  are a Devon based business run by Andrew Case BSc (Hons) C.Env CWEM MCIWEM, an experienced, qualified water quality scientist with over 18 years experience in the water industry.  We provide specialist chlorination/sterilisation/disinfection, testing and UKAS testing nationwide.  Our staff hold EUSR National Water Hygiene Cards and are we are WIAPS registered.  For further information or a quote please email or complete the form below.


Chlorination Certificate  Disinfection by chlorination is often a contract requirement for new internal plumbing prior to handover.  A chlorination certificate may also be needed for new 'over-sized' water pipes prior to a new water connection; before connection to mains pipe work the water company will need to see a chlorination certificate (to British Standards BS6700, BS EN 806 or BS8558) and if needed, the satisfactory sample results of a UKAS certified microbiology test.  Where needed a chlorination certificate can be provided on the same day.


Standard Chlorination Process

  1. Flush/swab pipe work/tank/reservoir.  Record background chlorine residual.
  2. Introduce 50ppm (mg/l) chlorine solution.
  3. Allow 50ppm chlorine to sit in contact for 1 hour.
  4. Flush pipe work until start chlorine level is reached, de-chlorinating water as necessary.  Test & record onsite parameters.
  5. If collecting a UKAS microbiological sample, wait 30 minutes prior to sample collection.


Chlorination equipment  We use  chlorine dosing equipment to ensure the correct chlorine residual throughout the length of the water pipe.  Onsite chlorine levels are electronically measured using a photometer and microbiological samples (if needed) are tested in an UKAS laboratory.  Materials, products and chemicals used are approved for use in contact with drinking water.  This includes ultra low bromate sodium hypochlorite.


Why is chlorination required?  The chlorination process ensures and demonstrates that the pipe work is hygienic and the water is free from contamination.  Chlorination is important for new installed pipe work, existing plumbing systems that have been out of use or where contamination is suspected. 


Chlorination advice  We will happily provide no-obligation free chlorination and disinfection advice - please contact us to  discuss your site requirements for a prompt estimate.


Last Minute/Same Day/Emergency Chlorination Certificate?  If you need a last minute, same day chlorination certificate, please give us a call to see if we can help.


Chlorination after prolonged period of non-use

The HSE document; Legionnaires’ disease Part 2: The control of legionella bacteria in hot and cold water systems details the actions to take when recommissioning plumbing systems taken out-of-use (and not regularly flushed).  Paragraph 2.52 on page 24 states that prior to ue the system should be treated as a new installation and cleaned, flushed and disinfected;


As well as commercial buildings, disinfection by chlorination should be considered for domestic properties such as those that have been unoccupied for a prolonged period prior to new owners/tenants.


Chlorination/disinfection/sterilisation/flushing services can also be provided for the following;

  • Tank chlorination
  • Office, Shop, restaurant and cafe shopfitting chlorination
  • Rental properties chlorination
  • Holiday park chlorination
  • Hotel chlorination
  • New domestic plumbing installations on new builds chlorination
  • New mains chlorination
  • Emergency chlorination
  • Commissioning of new buildings chlorination (frequent contract requirement)
  • Private water to mains conversions chlorination
  • Post major building extensions and alterations
  • After bacterial contamination
  • Legionella - disinfection to HSE ACOP L8 (Legionnaires' disease. The control of legionella bacteria in water systems)
  • Facilities management
  • Water system hygiene management
  • Systems not in regular use or flushed
  • Annual or routine system maintenance

Water company chlorination requirements and guidance - these are subject to change and are not the same across the UK water industry;

Chlorination Test Certificate

Your form message has been successfully sent.

You have entered the following data:

Chlorination quote

Please correct your input in the following fields:
Error while sending the form. Please try again later.

Note: Fields marked with * are required

Locations covered by Case Environmental include (but are not limited to);


Bedfordshire, Berkshire, Bristol, Buckinghamshire, Cambridgeshire, Cheshire, City of London, Cornwall, Cumbria, Derbyshire, Devon, Dorset, County Durham, East Riding of Yorkshire, East Sussex, Essex, Gloucestershire, Greater London, Greater Manchester, Hampshire, Herefordshire, Hertfordshire, Isle of Wight, Kent, Lancashire, Leicestershire, Lincolnshire, Merseyside, Norfolk, North Yorkshire, Northamptonshire, Northumberland, Nottinghamshire, Oxfordshire, Rutland, Shropshire, Somerset, South Yorkshire, Staffordshire, Suffolk, Surrey, Tyne and Wear, Warwickshire, West Midlands, West Sussex, West Yorkshire, Wiltshire, Worcestershire, Bath, Birmingham, Bradford, Brighton & Hove, Bristol, Carlisle, Cambridge, Canterbury, Chester, Chichester, Coventry, Derby, Durham, Ely, Exeter, Gloucester, Hereford, Kingston-upon-Hull, Lancaster, Leeds, Leicester, Lichfield, Lincoln, Liverpool, London, Manchester, Newcastle-upon-Tyne, Norwich, Nottingham, Oxford, Peterborough, Plymouth, Portsmouth, Preston, Ripon, Salford, Salisbury, Sheffield, Southampton, St Albans, Stoke-on-Trent, Sunderland, Truro, Wakefield, Wells, Westminster, Winchester, Wolverhampton, Worcester and York.



Blaenau Gwent, Bridgend, Caerphilly, Cardiff, Carmarthenshire, Ceredigion, Conwy, Denbighshire, Flintshire, Gwynedd, Isle of Anglesey, Merthyr Tydfil, Monmouthshire, Neath Port Talbot, Newport, Pembrokeshire, Powys, Rhondda Cynon Taff, Swansea, Torfaen, Vale of Glamorgan, Wrexham, Bangor, Cardiff, Newport, St Davids and Swansea.



Ayrshire, Dumfries and Galloway, Edinburgh and The Lothians, Glasgow and Clyde Valley and The Borders.


London Boroughs

Barking and Dagenham, Barnet, Bexley, Brent, Bromley, Camden, City of London, Croydon, Ealing, Enfield, Greenwich, Hackney, Hammersmith and Fulham, Haringey, Harrow, Havering, Hillingdon, Hounslow, Islington, Kensington and Chelsea, Kingston upon Thames, Lambeth, Lewisham, Merton, Newham, Redbridge, Richmond upon Thames, Southwark, Sutton, Tower Hamlets, Waltham Forest, Wandsworth and Westminster.


Water Companies

Affinity Water, Albion Water, Anglian Water, Bournemouth Water, Bristol Water, Cambridge Water Company, Cholderton and District Water Company, Dee Valley Water, Dŵr Cymru Welsh Water, Essex and Suffolk Water, Hartlepool Water, Northumbrian Water, Portsmouth Water, Severn Trent Water, South East Water, Southern Water, South Staffordshire Water, South West Water, Sutton and East Surrey Water, Thames Water, United Utilities, Wessex Water, Yorkshire Water and Youlgrave Waterworks.

Example Chlorination/Disinfection Certificate PDF
Example Chlorination Certificate.pdf
Adobe Acrobat document [270.8 KB]
Print Print | Sitemap
© Case Environmental


M: 07795 518 796

L: 01626 249 042